Hi. My two cents:
The implementation of tagged pointers has been *publicly available* for a long time in the CFLite source code from the Apple's Open Source website.
So, it is not something new, and the fact that there was a session with two minute talk about it at WWDC does not mean it became covered by the NDA instantly.
To add some pertinent detail, trade secrets are by definition not governed by copyright because they are unpublished. This is a double-edged sword; keeping a trade secret offers no protection from anyone else discovering the secret by legal means, but it also does not expire. If you are good at keeping your secret, you have an indefinite monopoly (examples are the formula for Coca-Cola as well as the seasonings for KFC chicken) - but anyone can legally duplicate it at any time and it is safe for them to do so. However - if a trade secret is misappropriated through improper means (like someone under NDA blabbing about it), the secret holder becomes legally entitled to certain forms of relief, such as a court imposing injunctions against use of the secret by the parties it was divulged to, financial damages, and more. In certain jurisdictions, like the US, revealing the secret is a crime in and of itself - in the US, it is a federal crime.
Most things I have been under NDA for have been so obvious that I don't know why they bothered, other than to keep corporate lawyers happy. Particularly for software, where it seems that similar ideas percolate to the surface independently and nearly simultaneously, keeping one's mouth shut is the surest way to keep options open for others. That consideration is of course in addition to the plain and simple ethics of sticking to both the letter and the spirit of any contract you have signed. If you can't or won't keep your promises, don't make them.
On Jun 15, 2013, at 6:24, Gregory Casamento <address@hidden
With NDAs there is no such thing as "fair use." What you're told at WWDC is usually considered trade secret information, particularly when they are giving you inside information about how something is implemented.
I am not a lawyer, so I am relying on my experience with such matters to discuss this. NDAs typically are built on what is considered to be proprietary or trade secret information. They typically don't cover what is considered to be "common knowledge" that is anything you created yourself without referring to the information covered in the NDA, anything someone else created without improper access to the trade secret information or anything that you can prove was commonly known to the general public.
That's why I was warning you. Typically it's dangerous to assume what is and is not covered without consulting someone